[SCSI] libfc: use rport timeout values for fcp recovery

Use the rport value for rec_tov for timeout values when
sending fcp commands. Currently, defaults are being used
which may or may not match the advertised values.

The default may cause i/o to timeout on networks that
set this value larger then the default value. To make
the timeout more configurable in the non-REC mode we
remove the FC_SCSI_ER_TIMEOUT completely allowing the
scsi-ml to do the timeout. This removes an unneeded
timer and allows the i/o timeout to be configured
using the scsi-ml knobs.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 42 insertions, 16 deletions

diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c
index 8eb67676d0dd..a7d956ad16e3 100644
--- a/drivers/scsi/libfc/fc_fcp.c
+++ b/drivers/scsi/libfc/fc_fcp.c
@@ -57,6 +57,9 @@ struct kmem_cache *scsi_pkt_cachep;
 #define FC_SRB_READ             (1 << 1)
 #define FC_SRB_WRITE            (1 << 0)
 
+/* constant added to e_d_tov timeout to get rec_tov value */
+#define REC_TOV_CONST           1
+
 /*
  * The SCp.ptr should be tested and set under the scsi_pkt_queue lock
  */
@@ -126,9 +129,7 @@ static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
 /*
  * Error recovery timeout values.
  */
-#define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 #define FC_SCSI_TM_TOV          (10 * HZ)
-#define FC_SCSI_REC_TOV         (2 * HZ)
 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 #define FC_CAN_QUEUE_PERIOD     (60 * HZ)
 
@@ -1083,6 +1084,21 @@ static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
 }
 
 /**
+ * get_fsp_rec_tov() - Helper function to get REC_TOV
+ * @fsp: the FCP packet
+ */
+static inline unsigned int get_fsp_rec_tov(struct fc_fcp_pkt *fsp)
+{
+        struct fc_rport *rport;
+        struct fc_rport_libfc_priv *rpriv;
+
+        rport = fsp->rport;
+        rpriv = rport->dd_data;
+
+        return rpriv->e_d_tov + REC_TOV_CONST;
+}
+
+/**
  * fc_fcp_cmd_send() - Send a FCP command
  * @lport: The local port to send the command on
  * @fsp:   The FCP packet the command is on
@@ -1099,6 +1115,7 @@ static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
         struct fc_rport_libfc_priv *rpriv;
         const size_t len = sizeof(fsp->cdb_cmd);
         int rc = 0;
+        unsigned int rec_tov;
 
         if (fc_fcp_lock_pkt(fsp))
                 return 0;
@@ -1129,10 +1146,12 @@ static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
         fsp->seq_ptr = seq;
         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
 
+        rec_tov = get_fsp_rec_tov(fsp);
+
         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
-        fc_fcp_timer_set(fsp,
-                         (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
-                         FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
+
+        if (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED)
+                fc_fcp_timer_set(fsp, rec_tov);
 unlock:
         fc_fcp_unlock_pkt(fsp);
         return rc;
@@ -1207,13 +1226,16 @@ static void fc_lun_reset_send(unsigned long data)
 {
         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
         struct fc_lport *lport = fsp->lp;
+        unsigned int rec_tov;
+
         if (lport->tt.fcp_cmd_send(lport, fsp, fc_tm_done)) {
                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
                         return;
                 if (fc_fcp_lock_pkt(fsp))
                         return;
+                rec_tov = get_fsp_rec_tov(fsp);
                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
-                fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+                fc_fcp_timer_set(fsp, rec_tov);
                 fc_fcp_unlock_pkt(fsp);
         }
 }
@@ -1351,9 +1373,6 @@ static void fc_fcp_timeout(unsigned long data)
 
         if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
                 fc_fcp_rec(fsp);
-        else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
-                               jiffies))
-                fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
         else if (fsp->state & FC_SRB_RCV_STATUS)
                 fc_fcp_complete_locked(fsp);
         else
@@ -1373,6 +1392,7 @@ static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
         struct fc_frame *fp;
         struct fc_rport *rport;
         struct fc_rport_libfc_priv *rpriv;
+        unsigned int rec_tov;
 
         lport = fsp->lp;
         rport = fsp->rport;
@@ -1383,6 +1403,9 @@ static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
                 fc_fcp_complete_locked(fsp);
                 return;
         }
+
+        rec_tov = get_fsp_rec_tov(fsp);
+
         fp = fc_fcp_frame_alloc(lport, sizeof(struct fc_els_rec));
         if (!fp)
                 goto retry;
@@ -1393,13 +1416,13 @@ static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
                        FC_FCTL_REQ, 0);
         if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC,
                                  fc_fcp_rec_resp, fsp,
-                                 jiffies_to_msecs(FC_SCSI_REC_TOV))) {
+                                 jiffies_to_msecs(rec_tov))) {
                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
                 return;
         }
 retry:
         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
-                fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+                fc_fcp_timer_set(fsp, rec_tov);
         else
                 fc_fcp_recovery(fsp, FC_TIMED_OUT);
 }
@@ -1455,7 +1478,6 @@ static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
                          * making progress.
                          */
                         rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
-                        fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
                         break;
                 case ELS_RJT_LOGIC:
                 case ELS_RJT_UNAB:
@@ -1508,12 +1530,12 @@ static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
                         }
                         fc_fcp_srr(fsp, r_ctl, offset);
                 } else if (e_stat & ESB_ST_SEQ_INIT) {
-
+                        unsigned int rec_tov = get_fsp_rec_tov(fsp);
                         /*
                          * The remote port has the initiative, so just
                          * keep waiting for it to complete.
                          */
-                        fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+                        fc_fcp_timer_set(fsp, rec_tov);
                 } else {
 
                         /*
@@ -1626,6 +1648,7 @@ static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
         struct fcp_srr *srr;
         struct fc_frame *fp;
         u8 cdb_op;
+        unsigned int rec_tov;
 
         rport = fsp->rport;
         rpriv = rport->dd_data;
@@ -1650,8 +1673,9 @@ static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
                        rpriv->local_port->port_id, FC_TYPE_FCP,
                        FC_FCTL_REQ, 0);
 
+        rec_tov = get_fsp_rec_tov(fsp);
         seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, NULL,
-                                      fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
+                                      fsp, jiffies_to_msecs(rec_tov));
         if (!seq)
                 goto retry;
 
@@ -1675,6 +1699,7 @@ static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 {
         struct fc_fcp_pkt *fsp = arg;
         struct fc_frame_header *fh;
+        unsigned int rec_tov;
 
         if (IS_ERR(fp)) {
                 fc_fcp_srr_error(fsp, fp);
@@ -1701,7 +1726,8 @@ static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
         switch (fc_frame_payload_op(fp)) {
         case ELS_LS_ACC:
                 fsp->recov_retry = 0;
-                fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
+                rec_tov = get_fsp_rec_tov(fsp);
+                fc_fcp_timer_set(fsp, rec_tov);
                 break;
         case ELS_LS_RJT:
         default: